Email updates

Keep up to date with the latest news and content from BMC Genomics and BioMed Central.

Open Access Highly Accessed Research article

Bos taurus genome assembly

Yue Liu1, Xiang Qin1, Xing-Zhi Henry Song1, Huaiyang Jiang1, Yufeng Shen12, K James Durbin13, Sigbjørn Lien4, Matthew Peter Kent4, Marte Sodeland4, Yanru Ren1, Lan Zhang1, Erica Sodergren15, Paul Havlak16, Kim C Worley1*, George M Weinstock15 and Richard A Gibbs1

Author Affiliations

1 Human Genome Sequencing Center, Department of Molecular and Human Genetics, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA

2 Department of Computer Science and Center for Computational Biology and Bioinformatics, Columbia University, New York, NY, USA

3 Department of Biomolecular Engineering, University of California at Santa Cruz, Santa Cruz, CA, 95064, USA

4 Centre for Integrative Genetics and Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, Arboretveien 6, Ås, 1432, Norway

5 Washington University St Louis, MO, USA

6 Department of Computer Science, University of Houston, 4800 Calhoun Road, Houston, TX 77204-3010, USA

For all author emails, please log on.

BMC Genomics 2009, 10:180  doi:10.1186/1471-2164-10-180

Published: 24 April 2009

Abstract

Background

We present here the assembly of the bovine genome. The assembly method combines the BAC plus WGS local assembly used for the rat and sea urchin with the whole genome shotgun (WGS) only assembly used for many other animal genomes including the rhesus macaque.

Results

The assembly process consisted of multiple phases: First, BACs were assembled with BAC generated sequence, then subsequently in combination with the individual overlapping WGS reads. Different assembly parameters were tested to separately optimize the performance for each BAC assembly of the BAC and WGS reads. In parallel, a second assembly was produced using only the WGS sequences and a global whole genome assembly method. The two assemblies were combined to create a more complete genome representation that retained the high quality BAC-based local assembly information, but with gaps between BACs filled in with the WGS-only assembly. Finally, the entire assembly was placed on chromosomes using the available map information.

Over 90% of the assembly is now placed on chromosomes. The estimated genome size is 2.87 Gb which represents a high degree of completeness, with 95% of the available EST sequences found in assembled contigs. The quality of the assembly was evaluated by comparison to 73 finished BACs, where the draft assembly covers between 92.5 and 100% (average 98.5%) of the finished BACs. The assembly contigs and scaffolds align linearly to the finished BACs, suggesting that misassemblies are rare. Genotyping and genetic mapping of 17,482 SNPs revealed that more than 99.2% were correctly positioned within the Btau_4.0 assembly, confirming the accuracy of the assembly.

Conclusion

The biological analysis of this bovine genome assembly is being published, and the sequence data is available to support future bovine research.